harmony, in music, simultaneous sounding of two or more tones and, especially, the study of chords and their relations. Harmony was the last in the development of what may be considered the basic elements of modern music—harmony, melody, rhythm, and tone quality or timbre. The polyphonic superposition (see polyphony; counterpoint) of horizontal melodic lines prevailed until the 16th cent., when the vertical or harmonic construction of chords was established. Rameau, in 1722, presented the idea that different groupings of the same notes were but inversions of the same chord. During the 18th cent. the concept of tonality, with the major and minor modes as its basis and with a certain chord serving as the key center of a composition, became general. The polyphonic music of Bach has a harmonic structure. As the system of triads and their relations was explored, the principle of modulation appeared, and composers developed freer concepts of tonality; Liszt, Wagner, and Richard Strauss greatly expanded the chordal vocabulary of tonal harmony. Finally, in the 20th cent., some have discarded tonality in favor of music that is composed in terms of horizontal contrapuntal lines. See atonality; serial music.

New Harmony, town (1990 pop. 846), Posey co., SW Ind., on the Wabash River; founded 1814 by the Harmony Society under George Rapp. In 1825 the Harmonists sold their holdings to Robert Owen and moved to Economy, Pa., where their sect survived into the early 1900s. Owen established a communistic colony in New Harmony that gained prominence as a cultural and scientific center and attracted many noted scientists, educators, and writers. Dissension arose, and in 1828 the community ceased to exist as a distinct enterprise, although the town remained an intellectual center. The nation's first kindergarten, first free public school, first free library, and first school with equal education for boys and girls were all established there. Some 25 Rappite buildings remain in New Harmony.

Harmony Society, religious society founded by German Separatists under the leadership of George Rapp. The Harmonists (or Rappites) held property in common and subscribed to the austere doctrines of their leader, including that of celibacy. In 1805 the society founded the village of Harmony, Pa., and developed it into a prosperous agricultural and industrial community. Led by Rapp, the Harmonists moved in 1814-15 to Indiana and founded another Harmony. They prospered there too, but in 1825 they sold their holdings to Robert Owen (see New Harmony) and returned to Pennsylvania to create their third village at Economy (now Ambridge), NW of Pittsburgh. In 1832 a part of the colony, under "Count Leon," a German adventurer, withdrew to form a separate community. The society was weakened by the death of Rapp (1847), dwindled as the members grew older, and went out of existence after 1906.

In music, the sound of two or more notes heard simultaneously. In a narrower sense harmony refers to the extensively developed system of chords and the rules that govern relations between them in Western music. Harmony has always existed as the “vertical” (the relationship between simultaneous melodic lines) aspect of older music that is primarily contrapuntal; the rules of counterpoint are intended to control consonance and dissonance, which are fundamental aspects of harmony. However, the sense of harmony as dominating the individual contrapuntal lines followed from the invention of the continuo circa 1600; the bass line became the generating force upon which harmonies were built. This approach was formalized in the 18th century in a treatise by Jean-Philippe Rameau, who argued that all harmony is based on the “root” or fundamental note of a chord. Tonality is principally a harmonic concept and is based not only on a seven-note scale of a given key but on a set of harmonic relations and progressions based on triads (three-note chords) drawn from the scale.

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